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097-55501-01 Revision M – January 2009
TimeHub 5500 User’s Guide
69
Chapter 2 Engineering Ordering Information
Card Overview
The LED status indicators on the Expansion Controller card are described in
When the Shelf Alarm LED is red, an alarm condition is detected by the Expansion
Controller card. The alarm is reported back through the Management card in the
master shelf. Specific alarms detected are:
Shelf Power A or B not detected. This illuminates the Alarm LED as well as
appropriate Shelf Power LED (red). Associated TL1 events are EXPWRA and
EXPWRB (Expansion Power Fail on terminal A or B).
The Expansion Controller card is receiving a good link but it is not associated
with its “preferred” master shelf clock.
The concept of a “preferred” Clock is used to better support redundancy. During
normal operation, each Expansion Controller card takes its clock from a different
Clock card. However, an Expansion Controller card can take its clock from either
Clock card so it is not critical that an EC card get its clock from its preferred source.
This alarm is reported simply to indicate the situation when this card is currently not
getting its clock from the preferred source. Specifically:
Table 2-9. Expansion Controller Card Front Panel Indicators
Indicator
Color
Description
Power
Green
On = The card is receiving power
Off = No power present
Fuse
Red
On = The Expansion Controller card fuse is open
Off = The Expansion Controller card fuse is not open
Shelf Alarm
Red
On = An alarm condition is present
Off = No alarm condition is present
Fail
Red
On = A hardware or firmware fault has occurred
Off = No hardware or firmware faults have occurred
Shelf Power
Green/Red
Green = Power is being successfully supplied to the
associated shelf power terminal (A or B)
Red = Power is not being successfully supplied to the
associated power terminal
Expansion Links
Green/Red
Green = Proper timing, framing, and communication is
coming from the Master shelf
Red = The link cable is attached but there is a problem
receiving either clock timing, clock framing, or
communication from the Master shelf
Off = The link cable is not connected, or the Clock
card(s) are in warmup mode